First-principles calculation analysis and photovoltaic properties of Cu compound-added perovskite solar cells

Abstract

Experiments and first-principles calculations were performed to investigate the effects of Cu substitution in CH3NH3PbI3 perovskite crystals. The first-principles calculations indicated that the energy level of the Cu d orbital formed above the VB maximum would be an acceptor or defect level. The effect of Cu addition on device properties was investigated, and the device with added 2% Cu provided higher efficiencies than the standard device. On the other hand, the decrease in short-circuit current density with increasing Cu content would be attributed to the defect level of the Cu d orbitals. First-principles calculations and experimental results provided insight into the function of Cu in CH3NH3-based perovskite crystals.

Effects of Copper Substitution in Methylammonium-Based Perovskite Solar Cells

“…The energy gap and carrier effective mass were calculated from the band structure, and the information on orbitals was obtained from the partial density of states (pDOS). The details of the calculation method are described in the previous papers [39].…”

“…In this study, the effects of the addition of Cu compounds to the perovskite precursor solution and the substitution of Pb with Cu on the device properties and electronic structure were investigated [39]. The amount of Cu added was varied in the range of 0, 1, 2, 3, and 12.5%, and the current-voltage characterization and X-ray diffraction measurements were performed.…”

Effects of alkali metals or Cu+ addition to α-FAPbI3 perovskite crystals on electronic structures and photovoltaic properties

“…[40][41][42][43] However, first-principles calculations and experiments have shown that the introduction of Cu 2+ into the B site in perovskite crystals destabilizes the crystal structure and reduces device stability. 44) For device durability, it was reported that the simultaneous addition of Cu 2+ and stable organic cations compensates the structural destabilization caused by Cu 2+ substitution. However, the Cu 2+ substitution affects the electronic structures, and the energy level of the Cu-d orbital formed in the forbidden band acts as a defect level, and the carrier recombination causes a decrease in short-circuit current density.…”

Effects of Co-Addition of Guanidinium and Cesium to CH3NH3PbI3 Perovskite Solar Cells

“…To stabilize the perovskite structures, various cations such as formamidinium (HC(NH 2 ) 2 , FA) [11,12], ethylammonium (CH 3 CH 2 NH 3 , EA) [13,14], or guanidinium (C(NH 2 ) 3 , GA) [15][16][17][18], which have larger ionic radii than MA, have been introduced at the MA site, and their stabilities were improved to a certain extent. The introduction of alkali metals such as cesium (Cs) [19][20][21], rubidium (Rb) [22][23][24], potassium (K) [25][26][27][28], and sodium (Na) [29][30][31] was also effective since these alkali elements do not desorb from the perovskite compounds.…”